1. Field of the Invention
The present invention relates to a document processing system for processing a print job to produce a document comprising at least one sheet, the print job having print job settings specifying a plurality of actions on a physical start product and specifying a desired end product, the document processing system comprising at least one printer and at least one finisher. The physical start product is at least one stack of sheets of at least one print medium type. The physical start product may be loaded in an input holder of the document processing system or inserted via an automatic document feeder of the document processing system.
The present invention further relates to a method for processing a print job in the document processing system according to the invention.
2. Description of Background Art
A document processing system is known to comprise a printer and one or more finishers. The printed sheets can be processed on one or more finishers to produce a variety of end products, like loose leaf documents, booklets, brochures, folders, perfect bound books, etc. Moreover, the sheets can be processed by one or more finishers before printing, for example pre-punching or pre-perforating. Hereinafter, finishing is understood to include finishing actions before printing and finishing actions after printing. Hereinafter finishing actions mentioned in any specification of finishing actions are to be envisioned, for example in a job definition format (JDF) specification.
The variety in finisher devices is large. Finishers may be in-line, online, near-line, or off-line. Finishers may provide only a single action like a guillotine trimmer or a series of actions like a perfect bound book maker. Finishers may have different operating ranges and constraints. The number of finishing actions is finite like folding, cutting, trimming, stapling, punching, creasing, etc. A finishing action is an operation on a sheet or on a stack of sheets or on an assembly of sheets, like a book block with a cover glued around it. An example of an enumeration of finishing actions is given in “JDF specification” Release 1.5—Dec. 31, 2013.
A document processing system is known to comprise a routing module for producing a production route model. A production route model consists of the selection of production devices to be used for the production of the required physical end product, and the determination of the sequence or network order in which to apply the production devices, and the settings to be applied to the production devices as part of the sequence or network order for producing the required physical end product. A production device is a printer or a finisher or any other device that is capable of participating in a production route model.
A document production system is known to comprise an imposition step. Imposition consists of the arrangement of page content of the incoming document to the sheets to be printed in such a way that the page content is positioned in the physical end product according to the intentions of the designer of the physical end product. Also, the imposition step may add marks to the imposition in such a way that the marks assist the operator(s) of the print production system to set up the print production equipment before the production actions are performed and to assist the operator(s) of the print production system to judge the quality of the set up after the production actions have been performed. Moreover, the imposition step may add information to the page content in such a way that the information assists the operator(s) of the print production equipment to identify the work in progress, to route the work in progress to a next production step and to identify the settings required by a next production step. Examples of such information are: file name, production date, order identifier, etc. Such information may be rendered in human readable form (like text or icon) and may be rendered in machine readable form (like barcode or QR code).
The imposition step has to comply with the production route model. When the imposition step does not comply with the selection of finishing devices or does not comply with the sequence or network of finishers or does not comply with the settings of the finishers, then the imposition step may position the page content at a position different from the one intended by the designer of the resulting physical end product, and the imposition step may position the marks at a position different from the one that would assist the operator in setting up the finishing device and in judging the quality.
Since the imposition step is performed separately from the creation of the production routing model, an error may occur if the imposition step does not comply with the production routing model. This also results in duplication of efforts, as the imposition step and the production routing model both involve a similar decision making process of how to produce a required physical output with the printing and finishing equipment available.
The imposition step may comprise a template mechanism. An imposition template is a predefined imposition that complies with a predefined production route model. A predefined production route model may contain predefined variations and hence the template must match these variations. The template mechanism fails if the imposition template does not comply with the production route model, or if the variations of the production route model are not properly propagated to variations in the imposition template. The template mechanism fails if a physical end product requires a production route model that falls outside the predefined variations of the predefined production route models. The template mechanism is time consuming to configure initially, and time consuming to maintain over time. It takes effort to validate the compliance of an imposition template and a predefined production route model, even more so if the predefined production route model contains a multitude of predefined variations.
A document processing system is known to comprise a spread preview. A spread is a pair of pages that can be observed simultaneously when leafing through a physical end product. A page is the side of a leaf. A leaf is the physical entity that is turned over when leafing through the physical end product. A spread preview is a representation of a spread for the purpose of visually checking that the physical end product will meet content placement criteria after production. Content placement criteria may include: a sequencing of page content over the pages, a position, an orientation and a scale of page content on the pages, an interference of binding artefacts with page content, and an interference of production tolerances with page content. Binding artefacts may include: holes in a sheet, limited ability to lay a document flat, a gutter between pages, visibility of a spine for wire-comb binding, etc. Production tolerances may include: image to sheet registration, a deviation between intended and actual property of an object such as sheet size, etc.
At present, the computations for a spread preview may be different from the computations for an imposition. This may lead to inconsistencies, where the spread preview does not show the imposition correctly.